Lumbar stenosis is a painful condition which compresses nerves and leads to back and leg pain. Traditionally this condition has been and is treated by a lumbar laminectomy with or without spinal fusion. A laminectomy entails the open surgical removal of lamina which decompresses the spinal canal and its nerves thereby alleviating symptoms. This procedure is done under general anesthesia, can be complicated by infection, spinal fluid leak, nerve injury, blood loss, infection etc. When a laminectomy is performed in conjunction with an instrumented pedicle screw fusion, the risks and complications are further increased, and are yet even further magnified in elderly individuals who commonly suffer from this condition.
Recent attention has been focused on minimally invasive techniques to alleviate lumbar stenosis. In particular, recent inventions include a variety of interspinous spacers which can be wedged in between spinous processes, and secured via adjustable wings to the adjacent SPs. This procedure keeps the adjacent SPs distracted even in the standing position, mimicking the flexed position, and hence in some cases relieves the symptoms of spinal stenosis. The most notable invention of this kind is the X-Stop (Zucherman et. al. Interspinous Process Apparatus and Method with a selectably expandable spacer; U.S. Pub. No. 2007/0093830 A1 Apr. 26, 2007) which consists of two adjustable wings attached to an adjustable interspinous spacer.
Applicants' related pending application Ser. No. 12/471,345, filed on May 22, 2009, application Ser. No. 12/471,340, filed on May 22, 2009, Ser. No. 12/054,335 filed on Mar. 24, 2008, Ser. No. 11/842,855, filed on Aug. 21, 2007, Ser. No. 11,536,815 filed on Sep. 29, 2006, and Ser. No. 11/208,644 filed on Aug. 23, 2005, each of which are hereby incorporated by reference, relate to interarticulating staples accomplishing Facet Joint (FJ), Spinous Process (SP), and Transverse Process (TP) fusion employing minimally invasive techniques. The embodiments described herein are modifications of a Spinous Process (SP) staple device, and incorporate interdigitating-interlocking hemi-spacers onto the top and bottom claws of the SP staple in between two sets of staple prongs which insert into two adjacent SPs. When the staple claws are clamped onto the two adjacent SPs, the intervening interlocked top and bottom claw hemi-spacers can unite to form a single spacer, and can be wedged in between the adjacent SPs, separating and distracting them, thereby relieving lumbar stenosis.
Placement of the exemplary devices can be done with local anesthesia, and through a small incision. As opposed to the X-stop, and similar devices, an exemplary device according to the invention is a one piece device (upon application) that merely has to be fastened onto adjacent SPs and clamped with a staple applier using a solitary one-step-procedure. This invention continues to further advance minimally invasive and low risk spinal device technology.